msm: msm_bus: Use uint64_t instead of int64_t for bimc_div parameter

Fix compilation warning caused due to comparison of distinct
pointer types lacks a cast error. While it is no request for
signed 64 bit when call bimc_div. So use uint64_t instead of int64_t.

Change-Id: Ib3756b9a4cb3824cdc286a08dbde78fc2a499302
Signed-off-by: Maria Yu <aiquny@codeaurora.org>